Adhesive



R. G. DREW Jan. 23j, '1940,

.ADHESIVE Original Filed' Dec. 12, 1929 Pa'tented'Jan. A23, 194.04

ADHESIVE Richard Gurley Drew, St. Paul, Minn., assigner to MinnesotaMining & Manufacturing Company,

tst. Paul, Minn., a corporation of Delaware Original applicationDecember 12, 1929, Serial No. 413,645. Divided and this applicationAugust 29, 1931, Serial No. 560,210

1o claims. (o1. isi-23.4)

My invention relates in general to adhesives, adhesive compositions oradhesive 'sheet or coatings, and more particularly to soluble adhesives,adhesive compositions or adhesive sheets or coatings, and still morespecically to heat .deformf able and energizable water solubleadhesives, adhesive compositions or adhesive sheets or coat-` ings andthe method of producing the same.

While the invention has,l a broad nele of usefulness, I have-found it ofpeculiar utility for producing an adhesive coating'for limiting theapplication of the spray of liquid nishing material, such as, forexample, lacquers or painting operations in automobile body paint shops,and

Iy therefore find it convenient to describe the invention in connectionwith such practice and.

product, it being understood, however, that such limited fields ofspecific description are employed purely for purposes of illustration ofan example Vof the utility of the invention in its severalphases,'beside such other novel elds of utility v asmay appear orhereinafter be pointed out.

lIn the work referred tospecifically above, my

improved material may be used as an adhesive for 'holding protectivepaper aprons against surfaces onwhich it is desired to apply thelacquer,

' paint, paint spray or lacquer spray, such as, for

example, glass windows, upholstery, rubber mats. on running boards,bright metal parts, covering and wrapping material in general, and thelike.

My improved product may also be applied to a surface which, in asubsequent step, is to be finished by an application of a lacquer sprayor` painting or to a surface whichhas been nished in order to preventminglingv of the colors as,'-

for example, in two-color work.

EMyimproved material may further-be applied i' to paper or othersuitable backing in the form.

of sheeted' material capable of being stored in piled sheets or in thelaminations as formed lby rolling the sheets', such as tape, or othersuchform as may bproper for the purpose contemplated. For certainpreferredwork, my imv proved material may be applied to paper to impartminimum point contact and inherent elasticity by applying they same topaper which is toweled or crimped or otherwise shaped, to present asurface other than flat and which has extensibility beyond that of theilat paper web. v

It is to be observed that' in finishing automobile bodies with lacquers,paints or the like of 'a plurality of colors, difficulty is found inlimiting the application, .owingto thedivision of the spray where suchis used. or requiring yskillful application of the paint brush when thelatter is used.

In. order to attain a clear and clean-,cut line of' demarkationv betweenseveral colors or within limited areas or applying a coating. materialwithin limited areas, masks in-the form of ladhesive tapes have beenused. These are of two general types, of which the zinc oxide tape andthe' rubber base tape form one group. both of which use a cloth backing,and the ordinary 'gumm-ed paper tape is an example of the other type.Both types of tape referred to present certain marked objections,amongst which may be' noted that the adhesive base thereon, such as thezinc oxide, is not water soluble and when re- -moved a; residue remainswhich has to be cleared away by some expensive organic solvent.Thisis"charaoteristic not only of zinc oxide but the rubber baseadhesives. Ordinary gum base tape is energized by wetting and, whenapplied to a surface, adheres so tenaciously thatto remove the samerequires soaking with water for a long time and further necessitatesscraping, ltending to' mar the underlying surface. Y

Furthermore, in the case of the tapes referred to, when applied to apaint coated object, it fre- A quently happens that in separating thetape from the surface,` patches of the paint will be lifted from thesurface and come away with the tape. Again, it frequently happens thatthese known tapes curl and become entangled in application and thereforebecome diicult'to manage and apply accurately. Similarly, if notcorrectly apl plied in the first instance, the retentive action of thesurface to which the tape is applied immediately prevents removal, inthis way not only marring the surface to which the tape is applied, butruining the same for reuse. Likewise, such tapes are often so energeticin their adhering action that the treated coat must be.

allowed to set and become firm before tape is apt plied thereto. e

' In the 'cases of covering certain materials, such as leather andglass, the known tapes are objectionable in Ithat they will not readilyadhere 'thereto or, if they are forced thereon by pressure,

the time element required to apply them and to thereafter clean orremove the same by reason of the adhesive enteringthe pores of theformer or becoming diffused thereover, as in the case of the latter,adds to the cost of operation and detracts ,from the result produced.Zit is further known that zinc oxide tape, rubberbase tape or gummedpaper tape tend to deteriorate with the .lapse of time, owing to thedrying out of the material and oxidation thereof due to atmospheric lexposure, with consequent loss of their power o1' adhering tothe objectto which-it is intended to be applied. v

While for simplicityv in A.describing the invention and as. an example fone method and means *for making the sainel I have referred to glue, itis tobe understood that I contemplate the employment of-,any adhesive.material suitabiet 'for my lpurposes and that I employ-the expressionglue in the specification and 4claims in its broadest sense as thatclass of adhesivematerials of organic and protein origin, and gumsserving the purpose contemplated by me. l

Among thev objects of my present invention ar the provision of anadhesive or coating material which is nondrying; the provision of anadhesive or coating material which is water soluble and energizable bythe action of heat; the provision of an adhesive or coating materialupona base of sheeted material such as paper, which is mild in its actionand energizable for application by exposure to heat; the provision ofan. adhesive or coating material upon a base such as paper which may beapplied to a lacquered, painted or varnished surface without injurythereof and. which is impermeable to freshly applied lacquer, paint orvarnish; the provision of an adhesive or coating material upon a basesuch as paper, cloth or the like that may be applied to leather or otherporous material Without infiltration thereof .and which is capable ofremoval therefrom Withoutv injury of the surface; the provision of anadhesive or coating material upon a base such as paper, cloth or lthelike, which may be applied by the application of heat and-simi larlyremoved therefrom for reuse; the provision of an adhesive for sheetedmaterial including paper, cloth or the like, which may be stored inpiles or laminations without the use of slip sheeting; the provision ofa sheeted material including paper, cloth or the like having an ad-Ahesive coating thereon whichmay be stored inY piles or laminationsWithout the use of slip sheeting and which is capable of being energizedwithout the application thereto of modifying ingredients but merely lbythe application of heat; the provision of a sheeted material includingpaper, cloth or the like which has an adhesive coating ,thereon andminimum point contact permitting ready removal thereof by forming thesame from creped material or toweled paper; the provision of a sheetedmaterial having an adhesive coating thereon and which is resilient,characterized by forming the same from creped or toweled paper; theprovision of a sheeted material having a. paper or like base treated torender the same `impermeable to coating materials such as lacquers,paints, varnishes orthe like; the provision of sheeted material having apaper base, treated whereby the same may be adhesively applied to asurface and removed without splitting of the paper; the provision of asheeted material having a paper base treated whereby an adhesive may beapplied thereto without permeating to the other side thereof; theprovision vof a sheeted material. having an uncalendered paper basesaturated with an adhesive material whereby one face thereof may beadhesively attached to a surface and separated therefrom withoutsplitting of the paper; the provision of a sheeted material having abibulous, uncalendered paper base saturated with an adhesive whereby anadherent coating may be appliedfand the s ame used for adhesivelyattaching the same to asurface by the application of pressure and to beseparated from such surface without tearing or splitting of the paper orleaving a riduum of the adhesive surface.

AMy invention still further has for an object thereof the provision of acoating composition adapted to form an adhesive surface energizable bythe application of heat or capable of being set by cold characterized byrapidly softening when subjected toheat and equally rapidly setting uponremoval of heat. l

The invention still further ha:4 for an object thereof the provision ofa material having a. paper base in which the lamentary material of `thepaper is locked and is resistant to tearing and splitting when incontact with an `adhesive surface; the provision of a sheeted materialhaving a paper base surface treated or saturated with a glue or gelatinebase composition, further treated to make the surface thereof stantiallynonadherent whereby an adhesiv,`

non-drying coating may be applied thereto, such as `a gelatine or gluebase adhesive, zinc oxide adhesive or rubber base adhesive, to providematerial capable of vbeing stacked, piled or rolled, y

without the use of intermediate slip sheeting.

To attain these objects and such further objects as may appear herein orbe hereinafter pointed out, I make reference to the accompanying drawingforming a part hereof, in which:

Figure 1 is a perspective view illustrating my invention as applied foruse in connection with a painters mask;

Figure 2 is a section taken on a line 2-2 of Figure 1.

In its preferred form my invention is embodied in a sheeted material inthe nature of a` tape I0 of a paper base saturated with a glue orgelatine base and coated on one face with a nondryingv adhesive II.In'this form, ,to apply the mask or apron I2 for painting or lacqueringoperations, a sheeted material which maybe paper or the like hasattached thereto adjacent the edges I3 along itslength a strip of tapeI0 by adhering the vadhesive coating thereto with a portion I4projecting beyond the edge |3, with' the adhesive surfaces II exposedupon the pro-I jecting portion I4. lThe projecting portion I4 maythereafter be applied to fasten the mask or apron wherever desired, theadhesive face II included by this projecting portion serving as themeans for attachment.

To prepare the tape I0 there is preferably rst provided a paper basewhich is preferably ab sorbent, approaching blotting paper, calenderedor uncalendered. Preferably, however, this paper base is of the unsized,uncalendered variety.

and is pressed, molded or otherwise formed to have the appearance oftoweled fabric, such as by crimping or crepeing the same. The paperso'provided is rst submitted td a preliminary treatment by a saturatingsolution involving 'a glue base. The saturating solution of thefollowing materials in proportions represent my preferred practice:

Pounds Dry glue 36 Water i '12 Glue solution (apprdx. 16 Twddde11) 10sComplete swelling is permitted, assisted by warming.

To this 1s then added 10a pounds of yellow A the back side.

tinuously submerged and passed through a bath ofthe saturating solutionas above prepared and then passed through pressure rolls to squeeze offthe excess and then dried by heating. It will be observed that justcomplete saturation is preferred as this step is closely related to thesuccess or failure of the treatment. An insufcient saturation will becharacterized by failure to completely bondthe fibres of the unsizedpaper nor will the saturating solution be present on IAn over-suiiicientlsaturation of the paper will render the surface unt for subsequentcoating, which will be observed as this description proceeds. K

A paper so treated will be found to havethe fibres thereof locked tomaterially strengthen the paper weband provide a highly exible sheet.Where I use the toweled or creped variety of paper, this sheet will befound to be substantially elastic and resistant to tearing by shock, aswhere using the same for wrapping purposes.

Prior to the drying step above mentioned', in one form of the practiceof my invention, after the paper has been saturated and passed throughthe pressure rolls, the web of material is subjected to a treatmenttending to insolubilize or tan the glue. The insolubilizing or tanningagents may be formaldehyde in solution orv as a vapor, sodium carbonatesolution or gallic and tannic acids, chromium trioxide and chrome alumor other chrome and aluminum salts.

My preferred practice is to submerge'the paper in a bath consistingofone part commercial formaldehyde and nine parts water by volume. Thelapse of time between saturating with glueglycerine water solution andformaldehyde does not seem to materially affect the quality of thepaper. Formaldehyding on one side only, that is, the application offormaldehyde to one face of the previously treated paperr is preferredfor purposes which will hereinafter appear where it is desired tofurther coat the untreated surface and leave the opposite surfacesubstantially inactive.

The formaldehyding on one face only has the advantage that immediateinsolubilizing or tanning may be practiced and further, treating oneside only is less strain on a paper than complete submersion,particularly where the formaldehyde is in the form of 'a solution andthe saturated paper before the'excess wateris evaporated is of lowtensile strength and therefore les subject to tear or break. The treatedsurface is then submitted to a neutralizing action and whereformaldehyde is used for the insolubilizing or tanning action, I mayaccomplish neutralization by subjecting the paper to a lime watertreatment. It is preferred, however, to submit the formaldehyded web toheat treatment. A temperature of 140 to 160 F. is used to thoroughly dryand volatilize all surplus formaldehyde.

It will be observed that I have described the saturation and theinsolubilizing or tanning of the glue base as separate steps. However,the tanning or insolubilizlng agent may be incorporated in thesaturating solution above described, the tanning action orinsolubilizing action of the glue being accomplished simultaneously withthe drying of the saturating solution. For the purpose there is added tothe saturating solution the tanningor insolubilizing agent. Where I useformaldehyde', I put an aldehyde compound into the glue solution priorto the saturation step. It :ls-preferred to retard the action of thealdehyde so that the insolubilizing or of the glue is accomplished inthe drying step. This retaraing activity is accomplished by taking anyaldehyde compound, such as formaldehyde, and

adding ammonia thereto. In practice, equalv molecular percentages offormaldehyde and ammonia are used in amounts equivalent to 5% l of thealdehyde to the dry weight of the. glue.

Thesaturating solution thus modified is used in the manner previouslydescribed. In the drying of the paper, the aldehyde-ammonia compoundbreaks` down to liberate formaldehyde, setting up, insolubilizing ortanning the glue.

Though mere'exposure by air 4drying of the saturated paper willsulciently insolubilize the glue, due to the decomposition oftheammonia- Iformaldehyde compound, to liberate formaldehyde, however, itisprefe'rred to hasten the de composition by heating the saturated web.Ordinarily a temperature of approximately 80 C. will be sufiicienlyrapid. However, it is preferred to use ay temperature between to 120 C.,which has been found to suiiiciently set the glue with a. speed ofoperation conducive to best practice.

The sheet so saturated andv heat treated will have the glue or gelatinebase substantially insoluble and, in a sense,I waterproof. 'I'he paperbase will be particularly strengthened and be resistant to' sudden shockor stress,l making it admirably suited for Wrapping purposes.Particularly desirable elastic properties will be obtained where thepaper base is of the toweled or creped variety wherein actual elasticityis imparted to the paper in that it retains the crimping or crepeingoriginally formed or molded in the paper and the tensile strength is`materially increased and is tougher in a wet state when carrying itsamount of water content, apparently due to a vulcanizing or gluingtogether of the fibres of the paper into a-solid mass. The

er flexibility augmenting agents as a modier` for the gluev in place ofthe glycerine may be used. For certain purposes, particularly as w-illhereinafter be described, sulphonated` oils such as Turkey red oil,sulphonated castor oil, may be used. 'These materials are nothygroscopic and tend to check, to a certain extent, the tendency toabsorb and carry too much water. While I may use hygroscopic agents ingeneral, for modifying the glue to retain a certain amount of watercontent inducing exibility, it is preferred to use organic modifiers andfor this purpose a sugar content fused in the glycerine of thesaturating liquid has been found to be particularly desirable.

A paper web saturated with the glue, formaldehyded ortanned as abovedescribed, has been found to be waterproof and particularly suitable asa base for forming the adhesive tape previous-- ly described when thereis coated thereover the non-drying adhesive I l. This non-drying ad-lhesive may be of the glue-gelatine variety or the 'zinc oxide base: orrubber base. `Thus, I -mayuse a water soluble coating or a waterinsoluble adhesive coating. The latter paricularly serves .to waterproofthe glue base saturated fabric.'

The waterproof coating may be heat enel-sizable .for adhesive purposesor prlmarily may be used as a waterproof coating'. For the latterpurpose, a Waterproof coating may be deposited upon the glue saturatedweb by dipping this web in a solution of asphaltum, removing the excesson the surface by means of pressure rolls. Although coating compositionssuch as parain,-Bakelite, drying oils, such'as linseed oil, andvarnishes may be used, asphaltum, because of its iiexible qualities andlow cost, is preferred. This coating may be of the tacky variety or ofthe more heat resistant variety. Where a bitumen base coating materialis used, a higher temperature resistant material may be obtained byblending gilsonite and Viscolt and applying them as a coating. The sheetso made with the waterproofing coating 4either of the adhesive varietyor primarily of the waterproofing varietyl may be used as awaterproofing wrapping paper capable of being stacked or piled withoutthe use of slip sheeting and is particularly tough, resilient andresistant to shock. r

Where I desire tov form the tape l with a nondrying adhesive Il of theWater soluble variety, the following coating composition serving as anadhesive has been found particularly desirable in a manner'whicli willbe apparent as this description proceeds.. 'I'he composition is asfollows:

, v Pounds Glue. (dry) 250 Water 250 Glycerine 7 50 Granulated sugar or75% of the dry glue weight. 1871/2 'I'his composition maybe made byswelling the glue with' a quantity of the specied water, assisted bywarming and thereafter the granulated sugar and glycerine are added withthe remaining quantity of water. The glycerine is used for itsflexibility augmenting and water retaining properties and the sugar isused not only because of its water retaining properties but because ofits viscosityaugmeiiting properties, further assisting in impartingcertain desirable features which will be hereinafter described. l

In general it is preferred to use as such viscosity augmenting and waterretaining agents, organic compositions. Of these there may be listed thefollowing:

(1) Sulphonated castor oil (2) Honey (crude or rened) (3) Paramn andother waxes (4) Gum chickle and other gums (5) Crude -glycerine (6)Small percentages of drying or non-drying oils (7) Venice turpentine (8)Shellac.

` use sugar and glycerine as the glue modifying agents, the adhesive isprepared as follows: the

quantity of glue is swelled in water, the action being facilitated bywarming. Separately, I fuse the sugar and glycerine content by mixingthe same at a temperature of about 250 F. The temperature is preferablyretained below 300 F. Temperatures in excess of 300 F. and up to 500 'F.will produce an entirely different result. The

Water-glue mixture and the sugar-glycerine mixture are then combined,preferably at the lower stated temperature. 'I'he material so preparedmay be spread upon any fabric webbing to obtainl base has impartedthereto increased body and viscosity. The adhesive has the ability tosharply react to the application of heat or removal thereof, causing theadhesive to be rapidly aggressive upon applicationvof heat, facilitatingits application wherever itis desired to be adhered and rapidly settingand staying in position vupon the removal of the heat. The compositionis particularly homogeneous and remains the same under most varyingchanges of atmospheric conditions.

In the preparation of the adhesive above described, the highest qualityhide glue has been found to be most practical for use in the productionof an adhesive best suited for a nondrying tape. Many kinds and gradesof glue may be used and still produce the desirable results, among whichmay be named the water soluble gums, such as tragacanth and acacia.Inferior glues .or hide and bone glues have certain valulablecharacteristics, among which is the possibility-of introducing solidmaterials without increasing the setting properties or jell strength ofthe adhesive. The working properties of the adhesive may thus becontrolled by the proper selection of the solid material in accordancewith the varyingclimatic and atmospheric conditions or to the moreparticular tastes of the user to modify the aggressiveness of theadhesive to render the same more rapid in its action or retard the same.These solid materials may be magneslum carbonate, lead oxide, Whiting,zinc oxide and what may be termed paint pigments.

' The adhesive as above made, particularly using the sugar-glycerinemodifiers, may be spread upon any webbing, cloth, paper or otherwise. It

is preferred, however, to spread this adhesive upon the glue saturatedpaper previously described, particularly that which has had aninsolubilizing or tanning treatment. The adhesive'has been found toadhere to the glue saturated paper treated yas above describedparticularly tenaciously and economy of this coating is effected by thenon-absorbent character of the -previously saturated paper for thisadhesive. The adhesive coating makes tenacious contact when a saturatedpaper base isused. Where insolubilized, tanned or formaldehydedglue'saturated paper is used with the adhesive coating, sheets of thismaterial may be stacked, piled or .rolled and it has been found that theback surface of the paper will not adhere to the underlying adhesivecoating, avoiding the necessity of intermediate slip sheeting. Forcertain purposes,

`tures are particularly desirable in that not only do they effecteconomy due to saving of the cost of the slip sheeting but where theadhesive is `made in the form of tape Wound in rolls, standard lengthsmay be provided in rolls considerably reduced in size.

The adhesive vabove described is preferably coatedupon the gluesaturated and formaldehyde treated paper'and will respond to warming toenergize its adhesive character or permit its removal and is alsocapableof stacking, piling or rolling without the use of slip sheeting. Forcertain purposes, however, the adhesive may be coated upon any paperbacking without the saturating and formaldehyding or insolubilizingtreatment. In such cases it is preferred to use an adhesive which hasbeen modified by solid materials such as the'magnesium carbonate, leadoxide, Whiting, paint pigments,.ground into the adhesive, to which ispreferably added such modiers as sulphonated oils. This form of adhesiveis preferably deprived of all excess moisture and may be'used on anuntreated paper backing or web of fabric without the use of liners orslip sheeting. This form of adhesive sheeting or tape becomesv'aggressive or adhesive upon'the application of heat, but is not asdesirable as the treated paper backing and adhesive coating in that itdoes not lend itself as readily to reuse upon reheating.

In general, it will Abe observed that 'I have provided an adhesive sheetor tape of the nondrying type which is susceptible of use without theaddition of modifying and preliminarily wetting agents and which may beapplied merely by the application of heat and similarly removed by thesame agency. The adhesive and the treated base lend themselves admirablysuitable 'for painting, lacquering or spraying operations.

'Ihey are impermeable and when. applied. on surfaces any residue may bereadily removed with water.

'Ihe specially treated paper and its adhesive coating duplicate resultsattainable heretofore only with cloth backing and. in addition, hasmarked advantages thereover. The paper base adhesive tape- (1) Producesa exible sheet .with more body and density than cloth, particularlywhere a creped or toweled paper is used;

(2) High tensile strength is obtained by loading the paper with glue,particularly' when coat-` ed upon by an insolubilizing, tanning orformaldehvding agent. f This renders the glue incapable of dissolving inwater, which permits it to retain a considerable amount of its strengthwhen in contact with water and 'hygroscopic materials which mayconstitute the adhesive film.

When glycerine or other modifying .elements are used, the saturatedsheet is particularly exible and resistant to breaking thereof bybending;

(3) The saturating and coating accomplish an action of welding,vulcanizing or gluing together of the paper fibres into one solid sheet,which makes impossible any laminating or splitting of the tape whenremoved from a surface to which it has been applied .for some time orwhen put up in rolls without the use of slip sheeting;

(4) The treatment, particularly the saturating heat, and quick insetting upon removal of heat,

l s treatmentof the' paper, particularly whenaccompanied bylnsolubilizing, tanning or formal-ri dehyding, ,also makes impossibleany '.surface, bres breaking away or tearing away from' the backing andsticking tothe adhesive lmwheniy" unwound from a roll. Thus, nomodification vof'.`

the adhesive film is effected. (5) The hygroscopic agent, such asglycerine retained in the saturated paper,l maintains aff water contentin the paper backing of which l0 i it is a part. The adhesive film istherefore prevented from anchoring itself toosecurely tothe reverse sideof the backing, that is, a non-drying adhesive secures a hold or adheresto a dry surface much more thoroughly than to-onewhich l@ is moist ordamp. Also, as the glue saturated paper hasbeen insolubilized, tanned orformaldehyded, the adhesive coating will not unite with the backing asthere is no solution possible between an untreated glue and aninsolubilized E gelatine.

This application is a division of my application Serial No. 413,645,substituted for my application Serial No. 182,893.

Having thus described my invention andv illustrated its use, what Iclaim as new and desire tosecure by-Letters Patent, is: y

1. An adhesive comprising a mixture of glue, 250 pounds; Water 250pounds; and apreliminary fused mixture 'of glycerine and sugarcomprising glycerine 750 pounds; and sugar 75% of the dry weight ofglue.

2. An adhesive comprising an aqueous-mixture l of a gelatinous materialand an organic viscosity augmenting agent chosen from the groupconsisting of sulphonated castor oil, honey,lwaxes including paramn,gums, including-gum chicle,

glycerine, drying or non-drying oils, Venice turpentine and shellac, theadhesive being'characterized by proportions of the organic viscosityaugmenting agent resulting in its non-'drying properties and sharplyreactive to heat to become aggressive in adhesiveness by the inclusionvof material percentages of sugar, preliminarily fused in theviscosityaugmenting agent and in quantities substantially '15% of the gelatinousmaterial and less than 25% of the viscosity auginenting agent.

3. An adhesive comprising an aqueous mixture of a gelatinous materialand an organic viscosity augmenting and water retaining agent,comprising sugar and glycerine, the adhesive being characterized byproportions of the materials resulting in persistence of its j ellproperties, responsiveness to heat, to become adhesively agressive andtenaciously adhesive to a fabric base and non-adhesive to aninsolubilized gelatinous surface, the sugar content being 'preliminarily25% of the glycerine content.

4. For use as a modifying composition for gelatinous materialsadapted torender the gelatinous material rapidly. adhesively aggressive to h'e'at,and quick in setting upon removal of heat, comprising a fused sugar andglycerine mixture. 5. For use as a modifying composition for gelatinousmaterials, adapted to render the gelatinous material rapidly adhesivelyaggressive to comprising a fused sugar and 'glycerine mixture. theglycerine being present in preponderating proportions.

6. For use as a modifying composition for gelatinous materials, adaptedto render the gelatuinous material rapidly adhesively aggressive toheat, and quick in setting upon removal of heat,

heat, the step which comprises preliminarily fusing sugar and glycerinebelow about 300 degrees Fahrenheit and .at a fusion'temperature above250 degrees Fahrenheit, the Iusiontbeing eiected before addition of thesugar and glycerine mixture to the gelatinous material.

9. An adhesive comprising a mixture of glue, water, sugar and glycerinein which the sugar and glycerine are preliminarilyfused and present inquantities rendering the adhesive rapidly aggressive togheat and settingupon removalof said heat.

10. An adhesive comprising a mixture of glue,

water, sugar and glycerine, the sugar and glycerine being present in apreliminarily fused mixture in quantities preponderatingly over theothercomponents, the adhesive being characterized by becoming rapidlyaggressive to heat and rapidly setting upon removal thereof.

RICHARD GURLEY DREW.

